Ladle flow control safety device for continuous casting machine

ABSTRACT

A continuous casting machine for molten steel requires a carefully controlled hydraulic head of molten steel for proper operation. The hydraulic head is provided by a tundish atop the continuous casting machine. The tundish in turn is supplied by a bottom pour ladle placed directly above the tundish and having an internal adjustable stopper rod for controlling the flow through the bottom tap or nozzle of the ladle. The invention comprises an auxiliary powered device which can move a separate external funnel or nozzle tightly up against the bottom of the ladle about the bottom tap to reduce the flow of metal from the ladle and thereby prevent overflow of the tundish with concurrent loss of molten metal when the stopper rod and nozzle of the ladle fail to operate and the flow from the ladle would otherwise exceed the requirements of the continuous casting machine.

United States Patent 1 1 Franklin LADLE FLOW CONTROL SAFETY DEVICE FOR CONTINUOUS CASTING MACHINE [76] Inventor: Arch V. Franklin, 2427 Dickenson,

Trenton, Mich. 48183 [22] Filed:

I June 19, 1972 [21] Appl. No.: 264,228

[52] vU.S. Cl 222/533, 164/152, 164/337,

222/547 [51] Int. Cl B22d 37/00 [58] Field of Search 164/136, 152,153,281,

164/337; 222/1, DIG. 26, DIG. 4, DIG. 21, 533,545,567, 160,166; 193/17 22,746 11/1914 Great Britain 222/D1G. l

[451 Jan. 21, 1975 549,212 ll/l942 Great Britain 1. ZZZ/DIG. 1 743,000 5/1933 France 222/166 Primary Examiner Robert B. Reeves Assistant Examiner-David A. Scherbel Attorney, Agent, or Firm-Farley, Forster & Farley 57 ABSTRACT A continuous casting machine for molten steel re quires a carefully controlled hydraulic head of molten steel for proper operation. The hydraulic head is provided by a tundish atop the continuous casting machine. The tundish in turn is supplied by a bottom pour ladle placed directly above the/tundish and having an internal adjustable, stopper rod for controlling the flow through the bottom tap or nozzle of the ladle. The invention comprises an auxiliary powered device which can move a separate external funnel or nozzle tightly up against the bottom of the ladle about the bottom tap to reduce the flow of metal from the ladle and thereby prevent overflow of the tundish with concurrent loss of molten, metal when the stopper rod and nozzle of the ladle fail to operate and the flow from the ladle would otherwise'exceed the requirements of the continuous casting machine.

12 Claims, 4 Drawing Figures PATENTED JANZI I975 SHEU 10F 2 PATENTEB JANZ 1 I975 SHEH 2 OF 2 1 LADLE FLOW CONTROL SAFETY DEVICE FOR CONTINUOUSCASTING MACHINE BACKGROUND OF THE INVENTION Continuous castin'g machines'have been long known in mean for'relatively lowmelting point metals. How ever," it has only been in} recent '"years that practical large scale continuous casting machines have been built and operated for steel because of the relatively high pouring temperatureand the'great tonnagecapacity that is required for economic production. For properoperation of 'thecontinuous casting machine, a controlled-"hydraulic.head of molten' steel is required at the. vertical inlet -'of thecontinuous 'casting machine.

This substantiallyconstant hydraulic headis provided I by atundishhaving a nozzle-in the-bottom leading into the continuous casting machine. The tundish has'a controllable stop'per rod inthe' nozzle. In normal operation, the tundish stopper rod'is'pulledand the molten steel inthe tundish continuously pours into the continuous casting maehine. lnorder to retain the proper hydraulic head-in the tundish,-arelatively larger supply of molten steel is positionedinabottompour ladle directly above the-tundish. Thisladle hasanozzle-in'the bottom tap anda ladle stopper rodinsertable in the nozzle to concally as often'as once a-day for each continuous casting I machine. Such failure -prevents the ladle stopper' rod from adequately reducing the flow of molten steel into the tundish thereby-causing overflow of the'tundish through an overflowspout provided thereon. Molten steel that overflows from the tundish'is'lost' from the casting process and must be scrapped andremelted. In addition, the ladle must bequickly moved from above the tundish and the-molten steel remaining in the ladle dumped into'a holding pit or other salvage device; Sin'ce a typicalladle for supplying a continuous casting machine contains upwards of 100 tons of molten steel, the failure of the ladle nozzle can'result in asubstantial loss of steel production and constitutes a substantial hazard to operating personnel adjacent'the continuous casting machine.

SUMMARY OF THE INVENTION The invention comprises a safety device located above the'tundish'and adjacent th'e bottomtap of the ladle during operation' 'of the-continuous casting ma-' chine. The device-is normally-in aretracted position wherein'itdoesnot interferewith the flow'of'molten tory lined nozzle which tightlyconta'cts the ladle substantially reducing-splash and restricting the flow of molten steel from the ladle. Alternately, the device may befitted with a plugged nozzle ,or refractory stopper to completely stop the flow of molten steel from the ladle and thereby effectively prevent molten steel from pouring into the tundish.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary view of a portion'of the continuous casting apparatus showing the location of the invention;

FIG. 2 is an enlarged bottom view of the invention;

FIG. 3- is a sectional side view of the invention taken along theline 3-3 of FIG. 2; and,

I 1 FIG. 4 is an end view of the invention taken in the direction 40f FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a tundish 1-0 is located above a continuous casting-machine (not shown) for casting molten steel.

For p'roper'operation, the level of molten steel in the tundish should be kept at ,a level indicated by the dotted line l2-to provide the proper hydraulic head and sufficient reservoir capacity for operation of the con-- tinuous casting machine. A ladle 14 is positioned above the tundish 10 to supply a continuous stream of molten steel indicated by l6'to the tundish. The ladle 14 is a bottom "tap ladle having arefractory lined nozzle 18 and a vertically movable internal stopper rod 20 to control the flow of molten steel through the nozzle 18. On either'side-of the ladle 14 are bridge girders'22 and 24 forming a part of the movable structure adapted to support a plurality of ladles and position them in turn above the continuous casting machine. The ladle 14 is supported in a ladle car which in turn is movable upon rails located on top of the bridge girders 22 and 24. The ladle car rails, and movable structure, not showmare well known in the art of continuous casting machinery.

The interior of the ladle 14 is lined with refractory brick and the nozzle 18 is usually cast of a refractory material. Supporting the refractory brick bottom of the ladle interior is a steel bottom 26 which includes an annular steel plate 28 surrounding and supporting the refractory' nozzle 18 which in turn extends through the annular plate28 as indicated at 30. During normal opthe event that the operator can no longer control the flow with'the stopper rod 20, applicants device, a portion of which is shown in FIG. 1 and generallydenoted steel fromthe bottom tapofthe-ladle. In the event the operator observes that the flow ofm'olten metal from the ladle is exceeding demand and the ladle stopper rod no longer can control the'flow, the operator then actuates the device which extends underneath the ladle and upwardly into'tight contact about the nozzle opening of the bottom'tap. The deviceincludes a separate refracby 32, will be extended under the ladle 14 as shown and upwardly against the annular plate 28 about the bottom 30 of the ladle nozzle 18.,

The preferred embodiment of the applicants device,

as shown'in FIGS. 2, 3 and 4, is hung below and attached to the bridge girder 22. A'bracket 34, welded or otherwise suitably attached to the bridgegirder 22, in turn'supports a bearing 36 as shown in FIG. 3. The. bearing 36in turn supports a vertical pivot 38 by means of a head '40 threaded thereon, and locked in place by means of a pin 42 or other suitable device to prevent the head 40 from disengaging the pivot 38. The lower end of the pivot 38 is welded at 44 to a large supporting plate 46. The supportingplate 46 is in contact with a roller 48 mounted upon a pivot 50 in turn attached to a bracket 52 welded or otherwise suitably fastened to the bridge girder 22. The supporting plate 46 is thereby free to rotate through a limited angle about the pivot 38.

Extending downwardly along opposite sides of the supporting plate 46 are side plates 54, best shown in FIGS. 2 and 4. The side plates 54 in turn support trunnion mounted rollers 56 engaging rail members '58, welded to side plates 60 of the extendable portion of the device. The side plates 60 are joined together by a horizontal flat plate 62. Thus, the horizontal plate 62, side plates 60 and rail members 58 can roll as a unit horizontally back and forth underneath the supporting plate 46. An air cylinder 64 is clamped by the hand operated clamping means66 to the supporting plate 46. The clamping means 66 extends through the gap 68 formed in the plate 62. The piston rod 70 of the air cylinder 64 is connected to a U-shaped, jaw 72 which rests upon a pin 74. The pin 74 in turn is supported by a bracket 76 in turn welded or otherwise suitably fastened to the plate 62. Actuation of the air cylinder 64 therefore can extend and retract the plate 62 and side plates 60 from under the supporting plate 46.

The side plates 60 extend upwardly at 78, to support a pivot pin 80 extending therebetween. The pivot pin 80 includes collar means .82 to retain the pin 80 in positionjoining the side plates 60. The pin 80 supports twin hooks 84. Extending between the twin hooks 84 is a T- shaped welded-shield plate assembly 86 which preferably is welded to both hooks 84 and retains them in proper position. The shield plate assembly 86 also deflects splashing molten steel away from the moving parts of the device located beneath the support plate 46. The head 40 on the pivot 38 is also preferably large enough to completely cover the bore hole thereunder and bearing 36thereby preventing molten steel, slag, or other debri from interfering with the bearing 36.

The hooks 84 are actuated to rotate about the pivot pin 80 by twin air cylinders 88, the piston rods of which are pivotally attached by a single pin 90 extending through and between the hooks 84. Collar means 92 are attached at either end of the pin 90 to retain it in proper position, joining the twin hooks 84. The body of each air cylinder 88 is pivotally attached by a pin 94 to a bracket 96 welded or otherwise suitably fastened to the plate 62. Thus, actuation of the air cylinders 88 will cause the twin hooks 84 to rotate and elevate upwardly. The hooks 84 include hook openings 98 extending upwardly and adapted to support trunnion pins 100 welded or otherwise suitably attached to a cup 102, preferably formed of 8" diameter steel pipe and having a bottom 104 welded thereto. Thus, upon actuation of the twin air cylinders 88 the cups 102 will be elevated. The bottom 104 has a hole 106 through which a funnel or nozzle 108 cast of refractory material extends. The refractory nozzle l08 is set in tire clay 110 inside the cup 102. A plurality of cups may be prepared with nozzles ahead of time and easily positioned or removed from the twin hooks 84. When the device is used, the refractory nozzle 108 will suffer from the errosive effects of the molten steel and therefore is intended for only one use.

The device normally remains in the retracted position shown in FIGS. 2 and 3 and is actuated to the operating position shown in FIG. 1 and in phantom in FIG. 3 when the ladle nozzle 18 fails during a pour from the ladle 14. Thus, the cups 102 need be exchanged only after pours where there has been a failure of the ladle nozzle 18. The upper opening end 111 of the cup nozzle 108 is large enough as shown in FIG. 2 to fit over the lower portion 30 of the ladle nozzle 18. This allows the cup 102 to tightly fit up against the annular plate 28 and thereby reduce to a minimum any splashing of molten steel when the device is used. In order to accommodate differences in position of the ladle which is movable as explained above with respect to the bridge girder 22 to which the device is fastened, handles 112 are fastened to each of the rail members 58. Thus, the operator can swivel the device about the pin 38 an amount sufficient to accommodate the position of the ladle 14. In addition the operator can position a hand operated clamp 114 at any suitable location on the side plate 54. The clamp 114 will engage the handle 112 and thereby provide an adjustable stop to determine the maximum extensionvof the device outwardly underneath the ladle 14.

As an alternative, the cup 102 may have a solid bottom 104 and refractory cup inside to stop the flow of molten steel entirely'or a refractory plug or ball may be inserted into the refractory nozzle 108 prior to use. Since the cups 102 are relatively small in size and weight, both the nozzle version and the refractory cup version may be kept at a conveniently close location for insertion into place just prior to use. As a second alternative the cup 102 may be replaced by a refractory plate which is thrust upwardly into tight engagement with the ladle nozzle bottom 30 to stop the flow of molten steel. With the flow from the ladle completely halted the movable structure can be actuated to move the ladle 14 and ladle car out of position without spillage of molten steel through the inoperative ladle nozzle 18.

The weight of the device is slightly biased horizontally about the pivot 38 to the right when retracted in order to retain engagement of the support plate 46 against-the roller 48. Additional weight may be added to either end of the device to adjust the balance and thereby provide ease of rotational movement with the cup extended but'not elevated into tight engagement with the ladle.

I claim:

l. A molten metal flow control safety device for use with a continuous casting machine supplied from a bottom tap ladle; comprising support-means positioned adjacent the ladle bottom, linear extension means mounted on and movable on the support means to extend under the'ladle upon actuation, means accommo-' dating lateral positioning of said extension means, flow control means mounted on said extension means, and means providing vertical positioning of said flow control means adapted upon actuation to engage said flow control means with the ladle bottom about the bottom tap.

2. The device of claim 1 wherein said flow control means comprises a cup circumferentially engageable about the bottom tap and containing a nozzle adapted to resist the temperature and erosive effects of flowing molten metal.

. ,3. The device of claim 2 wherein said flow control means include a refractory stopper adapted for insertion into the nozzle prior to actuation.

4. The device of claim 1 wherein said vertical positioning means includes fluid powered rotatable hookmeans adapted to support the flow control means.

5. The device of claim '4 wherein said flow control means includes trunnions adapted to rest in said hook means.

6. The device of claim 4 wherein said hook means includes shield means adapted to protect the fluid powered actuation means.

7. The device of claim 1 wherein said extension means is actuated by fluid poweredmeans.

8. The device of claim 1 wherein said lateral positioning means includes a vertical pivot on said support means to allow horizontal rotational positioning relative to a bottom tap ladle. v

.9. The device of claim 8 wherein said device is '6 slightly horizontally unbalanced toward said flow control means at saidvertical pivot when retracted.

10. The device of claim 8 wherein said device is slightly'horizontally unblanced toward said flow control means at said vertical pivot when extended.

11. The device of claim 1' wherein said flow control means comprises a refractory lined cup adapted to provide a complete stoppage of flow from a bottom tap ladle.

12. A molten metal flow control safety device comprising support means mounted upon a vertical pivot, linear extension means movable horizontally on the support means, elevating means rotatably mounted on the extension means, flow control meansmounted on the elevating means and adapted for engagement with the bottom tap of a ladle, and fluid powered means adapted to actuate the extension means and elevating means. 

1. A molten metal flow control safety device for use with a continuous casting machine supplied from a bottom tap ladle; comprising support means positioned adjacent the ladle bottom, linear extension means mounted on and movable on the support means to extend under the ladle upon actuation, means accommodating lateral positioning of said extension means, flow control means mounted on said extension means, and means providing vertical positioning of said flow control means adapted upon actuation to engage said flow control means with the ladle bottom about the bottom tap.
 2. The device of claim 1 wherein said flow control means comprises a cup circumferentially engageable about the bottom tap and containing a nozzle adapted to resist the temperature and erosive effects of flowing molten metal.
 3. The device of claim 2 wherein said flow control means include a refractory stopper adapted for insertion into the nozzle prior to actuation.
 4. The device of claim 1 wherein said vertical positioning means includes fluid powered rotatable hook means adapted to support the flow control means.
 5. The device of claim 4 wherein said flow control means includes trunnions adapted to rest in said hook means.
 6. The device of claim 4 wherein said hook means includes shield means adapted to protect the fluid powered actuation means.
 7. The device of claim 1 wherein said extension means is actuated by fluid powered means.
 8. The device of claim 1 wherein said lateral positioning means includes a vertical pivot on said support means to allow horizontal rotational positioning relative to a bottom tap ladle.
 9. The device of claim 8 wherein said device is slightly horizontally unbalanced toward Said flow control means at said vertical pivot when retracted.
 10. The device of claim 8 wherein said device is slightly horizontally unblanced toward said flow control means at said vertical pivot when extended.
 11. The device of claim 1 wherein said flow control means comprises a refractory lined cup adapted to provide a complete stoppage of flow from a bottom tap ladle.
 12. A molten metal flow control safety device comprising support means mounted upon a vertical pivot, linear extension means movable horizontally on the support means, elevating means rotatably mounted on the extension means, flow control means mounted on the elevating means and adapted for engagement with the bottom tap of a ladle, and fluid powered means adapted to actuate the extension means and elevating means. 